In Islam, one of two central techniques used in the development of Muslim Law, Sharia.With the art of developing new laws, fiqh, qiyas involved analogical reasoning as based on the two primary sources to Muslim Law, the Koran and the hadiths.The analogy of qiyas involved defining laws from a known injunction to a new injunction. An example to this would be when the established prohibition of alcohol (from the Koran) is used to prohibit the use of drugs which causes effects similar to the intoxication of alcohol.Although the meaning of qiyas now is clear, it was during the development of the first Muslim law schools often used in a very confusing manner. While Shafi'i would be the one to define the rules of fiqh, by including qiyas, he wrote in his "Risala" that "qiyas and ijtihad are two terms for the same idea." Still he would leave ijtihad out of the field of fiqh.Juridical problems that cannot be determined by qiyas, would be resolved through consensus, ijma, the other technique of fiqh.